Most of the matter making up the earth is composed of
A. gases
B. compounds
C. mixtures

Most of the matter making up earth is composed of compounds. I think

h

because u need two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei to form isotopes.

so since they all have the same shape? i mean maybe because m& m and reeses are both chocolates